Search results
Results from the WOW.Com Content Network
Lignite mining, western North Dakota, US (c. 1945). Lignite is brownish-black in color and has a carbon content of 60–70 percent on a dry ash-free basis. However, its inherent moisture content is sometimes as high as 75 percent [1] and its ash content ranges from 6–19 percent, compared with 6–12 percent for bituminous coal. [5]
There are other methods to increase nanoparticle penetration by skin damage: tape stripping is the process in which tape is applied to skin then lifted to remove the top layer of skin; skin abrasion is done by shaving the top 5–10 μm off the surface of the skin; chemical enhancement applies chemicals such as polyvinylpyrrolidone (PVP ...
The adult human body averages ~53% water. [7] This varies substantially by age, sex, and adiposity. In a large sample of adults of all ages and both sexes, the figure for water fraction by weight was found to be 48 ±6% for females and 58 ±8% water for males. [8]
In addition to natural processes, human activities strongly influence the chemical composition of aquatic systems and their water quality. [ 17 ] Allochthonous sources of carbon or nutrients come from outside the aquatic system (such as plant and soil material).
It is an oxidation product of lignite, associated with near-surface mining. [1] It is a rich source of humic acid (up to 90%) [ 2 ] and is used as a soil conditioner , as a stabilizer for ion-exchange resins in water treatment, [ 3 ] in the remediation of polluted environments and as a drilling additive. [ 4 ]
The Franz Cell apparatus consists of two chambers separated by a membrane of animal or human skin. Human skin is preferred but due to ethical and other considerations is not always available. Human skin often may come from autopsies or plastic surgeries. [20] The test product is applied to the membrane via the top chamber.
The primary site for ether cleavage is the α-carbon (carbon atom attached to the aromatic ring) of the propyl (linear three carbon) side chain. The following structures do not specify the structure since lignin and its derivatives are complex mixtures: the purpose is to give a general idea of the structure of lignosulfonates.
The human body is composed of approximately: 64% water, 20% protein, 10% fat, 1% carbohydrate, 5% minerals. [1] The decomposition of soft tissue is characterized by the breakdown of these macromolecules, and thus a large proportion of the decomposition products should reflect the amount of protein and fat content initially present in the body. [4]